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* [Bug middle-end/28367] accessing via union on a vector does not cause vec_extract to be used
[not found] <bug-28367-4@http.gcc.gnu.org/bugzilla/>
@ 2011-03-16 11:58 ` rguenth at gcc dot gnu.org
2014-10-10 0:25 ` glisse at gcc dot gnu.org
2014-11-24 9:03 ` rguenth at gcc dot gnu.org
2 siblings, 0 replies; 7+ messages in thread
From: rguenth at gcc dot gnu.org @ 2011-03-16 11:58 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28367
Richard Guenther <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |ASSIGNED
AssignedTo|unassigned at gcc dot |rguenth at gcc dot gnu.org
|gnu.org |
--- Comment #5 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-16 11:41:03 UTC ---
comment #1 is fixed, the original problem persists. optimized dump:
;; Function f (f)
f (vector(4) float t)
{
union
{
vector(4) float t1;
float t2[4];
} t5;
float D.2687;
<bb 2>:
t5.t1 = t_1(D);
D.2687_2 = t5.t2[0];
return D.2687_2;
}
FRE does not know how to handle different sizes in its support for
type-punning stores/loads (visit_reference_op_load).
Mine.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug middle-end/28367] accessing via union on a vector does not cause vec_extract to be used
[not found] <bug-28367-4@http.gcc.gnu.org/bugzilla/>
2011-03-16 11:58 ` [Bug middle-end/28367] accessing via union on a vector does not cause vec_extract to be used rguenth at gcc dot gnu.org
@ 2014-10-10 0:25 ` glisse at gcc dot gnu.org
2014-11-24 9:03 ` rguenth at gcc dot gnu.org
2 siblings, 0 replies; 7+ messages in thread
From: glisse at gcc dot gnu.org @ 2014-10-10 0:25 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=28367
Marc Glisse <glisse at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |glisse at gcc dot gnu.org
--- Comment #6 from Marc Glisse <glisse at gcc dot gnu.org> ---
Created attachment 33674
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33674&action=edit
rough patch
It needs more work (seems more complicated than it should be), but at least it
managed to produce what I expected for:
#include <x86intrin.h>
union u { __v4sf v; float a[4]; };
float f(__v4sf x){
u t;
t.v=x;
return t.a[2];
}
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug middle-end/28367] accessing via union on a vector does not cause vec_extract to be used
[not found] <bug-28367-4@http.gcc.gnu.org/bugzilla/>
2011-03-16 11:58 ` [Bug middle-end/28367] accessing via union on a vector does not cause vec_extract to be used rguenth at gcc dot gnu.org
2014-10-10 0:25 ` glisse at gcc dot gnu.org
@ 2014-11-24 9:03 ` rguenth at gcc dot gnu.org
2 siblings, 0 replies; 7+ messages in thread
From: rguenth at gcc dot gnu.org @ 2014-11-24 9:03 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=28367
--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
Yeah, something along that line would be needed. The issue is that
the partial value is not "available" (as in: it doesn't have a SSA name)
and thus there is nothing to CSE the load to.
I suppose that we should generalize this support for real-/imag-part of
complex values as well. Not sure if it is worth using BIT_FIELD_REF
for getting at pieces of scalar registers (maybe it would pay off for
targets that can efficiently compute lowpart subregs).
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug middle-end/28367] accessing via union on a vector does not cause vec_extract to be used
2006-07-13 2:43 [Bug middle-end/28367] New: " pinskia at gcc dot gnu dot org
` (2 preceding siblings ...)
2006-07-19 14:46 ` pinskia at gcc dot gnu dot org
@ 2006-08-26 4:48 ` pinskia at gcc dot gnu dot org
3 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-08-26 4:48 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from pinskia at gcc dot gnu dot org 2006-08-26 04:48 -------
This is not target specific.
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
GCC target triplet|powerpc-linux-gnu |
Last reconfirmed|0000-00-00 00:00:00 |2006-08-26 04:48:03
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28367
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug middle-end/28367] accessing via union on a vector does not cause vec_extract to be used
2006-07-13 2:43 [Bug middle-end/28367] New: " pinskia at gcc dot gnu dot org
2006-07-13 5:37 ` [Bug middle-end/28367] " pinskia at gcc dot gnu dot org
2006-07-14 7:58 ` pinskia at gcc dot gnu dot org
@ 2006-07-19 14:46 ` pinskia at gcc dot gnu dot org
2006-08-26 4:48 ` pinskia at gcc dot gnu dot org
3 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-07-19 14:46 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from pinskia at gcc dot gnu dot org 2006-07-19 14:46 -------
(In reply to comment #2)
> I have a patch to fix that related testcase and also fix some other issues
> related to BIT_FIELD_EXPR expansion with vec_extract (and why vec_set is still
> unused after my patch too).
And I filed it as PR 28436.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28367
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug middle-end/28367] accessing via union on a vector does not cause vec_extract to be used
2006-07-13 2:43 [Bug middle-end/28367] New: " pinskia at gcc dot gnu dot org
2006-07-13 5:37 ` [Bug middle-end/28367] " pinskia at gcc dot gnu dot org
@ 2006-07-14 7:58 ` pinskia at gcc dot gnu dot org
2006-07-19 14:46 ` pinskia at gcc dot gnu dot org
2006-08-26 4:48 ` pinskia at gcc dot gnu dot org
3 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-07-14 7:58 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from pinskia at gcc dot gnu dot org 2006-07-14 07:58 -------
(In reply to comment #1)
> Note a related testcase is:
I have a patch to fix that related testcase and also fix some other issues
related to BIT_FIELD_EXPR expansion with vec_extract (and why vec_set is still
unused after my patch too).
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28367
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug middle-end/28367] accessing via union on a vector does not cause vec_extract to be used
2006-07-13 2:43 [Bug middle-end/28367] New: " pinskia at gcc dot gnu dot org
@ 2006-07-13 5:37 ` pinskia at gcc dot gnu dot org
2006-07-14 7:58 ` pinskia at gcc dot gnu dot org
` (2 subsequent siblings)
3 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-07-13 5:37 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from pinskia at gcc dot gnu dot org 2006-07-13 05:37 -------
Note a related testcase is:
#define vector __attribute__((vector_size(16)))
float f(vector float t)
{
return *(float*)(&t);
}
Which is only mentioned here in get_alias_set in the GCC sources as being not
violating aliasing rules (see also
http://gcc.gnu.org/ml/gcc/2006-07/msg00250.html).
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28367
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2014-11-24 9:03 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
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[not found] <bug-28367-4@http.gcc.gnu.org/bugzilla/>
2011-03-16 11:58 ` [Bug middle-end/28367] accessing via union on a vector does not cause vec_extract to be used rguenth at gcc dot gnu.org
2014-10-10 0:25 ` glisse at gcc dot gnu.org
2014-11-24 9:03 ` rguenth at gcc dot gnu.org
2006-07-13 2:43 [Bug middle-end/28367] New: " pinskia at gcc dot gnu dot org
2006-07-13 5:37 ` [Bug middle-end/28367] " pinskia at gcc dot gnu dot org
2006-07-14 7:58 ` pinskia at gcc dot gnu dot org
2006-07-19 14:46 ` pinskia at gcc dot gnu dot org
2006-08-26 4:48 ` pinskia at gcc dot gnu dot org
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